Marine: Boating, Sailing, PWC, GPS and Navigation - Boat won't start since hurricane

My 89 Bayliner OMC Cobra ran beautifully right before the Sept. '04 hurricanes struck. When I checked the boat a month after the storms, I couldn't get her to start. I've drained 3 batteries trying to get it to turn over and stay running. Well, 8 months later I still can't get it to start and now I'm afraid that leaving her untouched (on a trailer) has made things worse. I finally have some time (plus some summer-time incentive) to get this fixed. Any suggestions on what to check first and what might have happened to it.....is it possible that something got wet, that shouldnt have, from all that hurricane rain? Also, did I further mess up the boat because of not starting it in 8 months?

You only need 3 things to make a motor run, spark, air and fuel. Pull the plugs and replace, replace the distributor cap and rotor, replace the fuel filter. Now the harder part...you need to check your fuel to see if you have water in it. You will need a thin stick. Go to an auto parts house and get the "water in fuel" test goop. Sorry I don't remember what it's called. It is a goop you spread on the stick and then dip it in your fuel tank. If water is present it will change colors. Or you could just drain the tank and refill. Also add some stabilizer.
Ohh and while you have the plugs out, spray some defogger or WD-40 in the cylinders. Next change the oil and water impeller, check the belts, bilge pump, fluid levels and all electrical connections and we can call it a good spring checkup.
Good luck.

Thank you TxTaz for your help. I'll try those things you mentioned and will post the results. You're a lifesaver! :D